Known in the art is a bipolar biactive electrocoagulator, comprising a cylinder one of whose end faces carries two electrodes, a flat end face of said cylinder serving as the working portion of such an electrocoagulator. A power source is connected to the electrodes through current leads, which feeds a radio-frequency current flowing between the electrodes through portions of living tissue during surgery (cf., e.g., "General Physiotherapy" by Ye. I. Pasynkov, Moscow, Medgiz Publishers, 1962 (in Russian).
Such an electrocoagulator features too a small effective area in contact with the tissues being operated, whereby to apply a hemostatic effect to a rather large area requires a prolonged length of time. This, in turn, extends operating time and causes heavy blood loss. Moreover, carbon deposit on the electrodes affects adversely the intensity of an r.f. electrical field so that blood coagulation ceases.
To restore normal operation of the instrument rather frequent cleaning of the electrodes from carbon deposit is required.
In addition, the aforementioned coagulator is inapplicable for producing hemostasis in hard-of-access places of human body, such as "pockets" or "pouches", ducts, depressions, caves, and some other structures in patients' living tissue.
Known in the art are also bipolar monoactive electrocoagulators, each comprising two electrodes of which one is shaped as a plate and the other, as a segment. Both of the electrodes are connected to an r.f. voltage source (cf., e.g., a catalogue "Medical instruments, apparatus, devices and equipment", Book 2, 1961).